The invention concerns a device for supporting an electric motor driving a turbine, notably for heating and/or air conditioning equipment in a motor vehicle.
It concerns more particularly a device of the type comprising a cage formed so as to delimit a housing for receiving the casing of the motor, which opens out into a shell for receiving the turbine, the housing comprising a base wall connected to a peripheral wall, itself connected to a substantially annular front wall forming part of the shell, and in which the peripheral wall is interrupted in order to define at least one channel for cooling the motor, the said cooling channel being delimited by two opposite lateral walls which extend in a substantially radial direction with respect to the axis of rotation of the motor.
A device of this type is disclosed by the publication FR-A-2 412 976.
The motor/turbine assembly, also referred to as a "motorized fan", is designed to blow out a flow of air coming from outside the passenger compartment of the vehicle or a flow of air recirculated from the passenger compartment in order then to send it into the passenger compartment after having been heated or cooled by a suitable heat exchanger.
The cooling channel or channels formed in the cage supporting the motor are designed to divert a proportion of the air flow moved by the turbine, so as to cool the electric motor. Generally the cage delimits two opposite cooling channels. As a result of this a proportion of the air flow enters a channel which serves as an air inlet, then sweeps the parts of the motor to be cooled and is discharged through the other channel, which serves as a discharge channel.
The support devices known up to the present time do not always give complete satisfaction since they very often generate a high noise level, which impairs the comfort of use of the heating and/or air conditioning equipment.
This noise level is due partly to the acoustic radiation from the support and shell excited by the vibrations generated by the motor, and partly to the turbulences in the air flow which enter the cooling channels.
Moreover, they do not provide correct guidance of the air flow used for cooling the electric motor.
Another problem associated with this type of device lies in the fact that it is necessary, on each occasion, to provide a different cage according to the direction of rotation of the turbine, the latter being dependent on the vehicle on which the heating and/or air conditioning equipment is to be installed. This is because, up to the present time, it is necessary to provide different directions of rotation depending on whether the equipment is intended for a vehicle with right-hand drive or a vehicle with left-hand drive, or according to the internal arrangement of the components making it up.